Originally Posted by EWR764

Think it's an aircraft availability issue. There are plenty of 767s to go around in EWR, but since it is not yet a 787 pilot domicile, the airplanes and flight crews are probably coming on a six-day rotation from IAH, e.g. day 1 IAH-LHR, day 2 layover, day 3 LHR-EWR, layover, day 4 EWR-LHR, day 5 layover, day 6 LHR-IAH.

The three-cabin F birds are primarily there to drive full-fare J traffic, which GS/1K can upgrade with a SWU, and because those airplanes are in a rather premium-heavy configuration. So, TXL makes more sense because it is more business-oriented. OTOH, in a market like LIS, the higher density of the 2-cabin 763ER is necessary.